province = {'hunan': {'hengyang': 'hengshan'}, ' guangdong': {'shenzhen': 'baoan'}, 'beijing': {'beijing': 'chaoyang'}}
print("这里有这些省份：hunan\nbeijing\nguangdong")
inp = input("请输入你选择的省份：")
a = list(province['{}'.format(inp)])
print('这里有这些城市：{}'.format(a[0]))
inc = input("请输入你选择的城市：")
print('这里有这些县：{}'.format(province['{}'.format(inp)]['{}'.format(inc)]))